Engine control apparatus



Nov. 17, 1936. c. I. McNElL ENGINE CONTROL APPARATUS Filed Sept. 13, 1932 TO IGNITION svs'rem INVEN TOR. Char/ea 0/ /1421? %a A EY.

Patented Nov. 17, 1936 UNITED STATES PATENT OFFICE mesne assignments, to poration, East Orange, New Jersey Eclipse Aviation Cor- N. J., a corporation of Application September 13, 1932, Serial No. 633,000

5 Claims.

This invention relates to engine control apparatus and particularly to means for automatically controlling the supply of fuel to an internal combustion engine' An object of the invention is to provide means for controlling the automatic operation of the throttle valve of an internal combustion engine in accordance with the pressure prevailing in some chamber, such ,as the intake manifold, through which the fuel charge passes on its way to the combustion chamber or chambers of the engine.

Another object of the invention is to provide combined pressure and temperature responsive means for controlling the setting of the engine throttle valve.

A further object of the invention is to provide combined thermo-electric and electro-magnetic means for controlling the setting of the engine throttle valve.

A further object of the invention is to provide means operative after the lapse of a predetermined time interval, measured from the time of closure of the engine ignition circuit, for varying the setting of the engine throttle valve.

These and other objects and advantages to .be derived from the use of the invention herein disclosed involve the inter-relation and relative functions of the parts, and will become apparent upon an inspection of the following specification and the accompanying drawing, wherein the preferred embodiment of the invention is disclosed. It is to be understood, however, that the drawing is for the purpose of illustration only and is not designed .as a definition of the limits of the invention, reference being had for such purpose to the appended claims.

The drawing shows a schematic representation of the novel instrumentalities in which the present invention may be embodied,

In the drawing, the invention is shown applied to a throttle valve 6 located in the carburetor or other conduit I joined by a flange 8 to the intake manifold 9 of an internal combustion engine (not completely shown) the throttle valve being shown as of the usual type involving a circular disc mounted on the pin H adapted to be oscillated by reason of the connection therewith of an arm 12 which is attached by a pin and slot connection as indicated at 25, to the usual accelerator link l3; the arm i2 being normally held against a stop l6 by the action of a tension spring ll anchored to the conduit 1 as indicated at l8 and connected to a projection of the arm l2, as indicated at I9.

' rent flowing through the The combined pressure and temperature responsive means for moving the throttle against the tension of spring l1, preferably takes the form of a heating coil 22 connected with an electrical circuit leading from a suitable source of 5 current, such as a battery 23, and closable by operation of any suitable switch means, such as indicated at 24, constituting also the means for closing the circuit to the ignition system, only one lead 26 of which is indicated in the drawing, as the ignition system per se forms no part of the present invention. A suitable resistance coil 21, may, if desired, be interposed between the leads 28 and 29 connecting the battery with the heating coil 22, said resistance being shown as in shunt with the winding 3| of an electro-magnetic device herein shown as a solenoid having a magnetizable core or plunger 32 provided with a fixed collar adapted to contact with a stop member 2| to limit the movement of valve 6 20 when the solenoid is energized. The outer end of the plunger is apertured as indicated at 33 for reception of one end of a flexible connection herein shown .as a cable l4 with its opposite end attached to the arm l2 as indicated at [5.

As shown the heating coil 22 is wound about a bi-metallic strip 36 secured to, and insulated from, as indicated at 31, a bracket 38 extending from a cup-shaped element 39 which, together with the flexible diaphragm 40, forms a sealed chamber permanently in communication with the intake manifold 9 by virtue of the interconnecting conduit 4|. As shown, the circuits to both the winding 3| and heating coil 22 pass'by way of the cup-shaped element 39 to the conductor 41 leading to the ground 48, the other side of the battery being also grounded as indicated at 49. At the lower end of the bi-metallic strip 36 there is provided a current conducting contact 5|, the flexure of the strip being such that 4 under normal conditions (that is, with no curheating coil 22) contact 51 is in engagement with a corresponding contact 53 mounted at the center of the flexible diaphragm 40. Preferably the setting is such that the diaphragm movement is not enough, in itself, to open the contacts, and the arm 36 is preferably so arranged that it follows the diaphragm and thus maintains the circuit closed until the current has been flowing through the heating coil for a given period of time.

Having thus described the parts entering into the preferred embodiment of the invention shown, the operation thereof will be seen to be as follows:

Upon closing the ignition switch 24 current flows from the battery 23 to line 26 and the resistor 21 and heating coil 22, which slowly heats the bi-metallic arm 36 carrying contact At the same time current flows through traction solenoid 3|, lead 35, arm 36, contacts 5!, 53 and diaphragm 40 to ground, completing the battery circuit. This current passing through the solenoid creates a magnetic pull which attracts plunger 32 and moves it to the left as viewed in the drawing (until collar 20 abuts stop member 2|) and opens the throttle sufiiciently to permit the induction into the engine, of a sufficient fuel charge for starting purposes. The throttle then remains in this position until contacts 5| and 53 are separated by the heat-induced flexure of arm 36, aided by the increase in the degree of intake manifold vacuum which occurs as soon as theengine starts. At any time thereafter when the manifold vacuum falls below some predetermined point (such as would happen immediately preceding a stall) the resulting increased pressure on the diaphragm will cause the contact 53 to movetoward the left as shown in the drawing, to again close the circuit through arm 36, and the solenoid 3! to open the throttle and prevent the stall from taking place.

There is thus disclosed a novel engine control mechanism whereby the supply of fuel under the control of combined pressure and temperature responsive means is so inter-related as to function properly to vary the setting of the throttle valve automatically as the varying conditions require.

As above explained, the mechanical construction of the individual elements controlled by the novel mechanism herein disclosed may vary as desired, as may also the trically and electro-magnetically inter-relating the controls therefor, provided one or more of the essential features of the system are retained. Likewise other changes, substitutions, and omissions may be made within the scope of the broadest of the appended claims.

What is claimed is: t I

1. In combination with an internal combustion engine having a fuel intake conduit and a variable volume chamber in constant communication therewith, a flexible diaphragm forming a part of said. chamber, means responsive to a predetermind temperature rise and coincident movement of said diaphragm for varying the eflfective cross-sectional area of said intake conduit and precise method of electhereby controllingthe amount of fuel drawn therethrough, said last named means comprising a throttle valve and an electro-magnetic device for shifting said throttle valve, and means mounted on said diaphragm for controlling the energization of said electro-magnetic device.

2. In combination with an internal combustion engine having a .fuel intake conduit, a throttle valve therein, electro-magnetic means for shifting said throttle valve, means responsive to the closing of the ignition circuit of the engine for initially energizing said electro-magnetic means, and pressure responsive means operative only after the lapse of a predetermined time interval following such initial energization for de-energizing said electro-magnetic means.

3. In combination with an internal combustion engine having a fuel intake conduit, a'throttle valve therein, electro-magnetic means for shifting said throttle valve, means responsive to the closing of the ignition circuit of the engine for initially energizing said electro-magnetic means, and combined temperature and pressure responsive means for de-energizing said-electro-magbeing efiective only in the event that said first named means has operated to decrease the chamber volume. a

5. In combination with an internal combustion engine having an ignition circuit, a fuel intake conduit, a throttle valve therein, and a variable volume chamber, means responsive to a drop in intake conduit pressure to decrease the volume of said chamber, means responsive to closure of the ignition circuit to exert an actuating pull on said throttle valve, and means for releasing said actuating pull after the ignition circuit has been closed for a definite period, said releasing means being effective only in the'event that said first named means has operated to decrease the chamber volume. 

